1. The Field of the Invention
The present invention is related to wheel hubs. More particularly, the present invention is related to a lightweight wheel hub which includes annular bearing assemblies which engage the ends of a substantially hollow axle. The wheel hub also has a pair of stops positioned within the axle of the wheel to provide a means of attachment to a bike frame and to offer stability.
2. Technical Background
An important consideration for users and manufacturers of high-end performance bicycles is the weight of the bicycle. A lighter bike reacts faster to rider input and it takes less of the rider's energy to power a lighter bicycle. Simply stated, the lighter the bicycle weighs, the easier it is to maneuver and the better the performance that can be obtained from the bicycle. Thus, manufacturers of cutting edge performance bicycles are continuously upgrading their bicycles to decrease weight.
One obvious way to reduce the weight of a bicycle is to use bicycle parts made of lighter materials. Another way to reduce the weight of a bicycle is to simplify the design of bicycle part so that it can be manufactured using less material. This can be done by economizing or combining the function of multiple pieces such that one piece can perform the function of what was formerly required of two or more pieces.
An area of the bicycle where the function of separate parts could be combined, thereby reducing the amount of material needed, is in the wheel hub. Many wheel hubs comprise a hollow axle with a pair of annular bearing assemblies positioned concentrically over the axle and a hollow cylindrical shell. The bearing assemblies are prevented from inward movement along the axle by the hollow cylindrical shell enclosed about the axle which acts as a spacer between the bearing assemblies. Each end of the shell engages a respective bearing assembly to maintain the bearing assembly in a spaced relationship.
In other wheel hub designs, a hollow shell with raised ends is positioned over the axle between the bearing assemblies. The raised ends provide a way to attach the hub to a wheel rim using spokes or other means.
Still other designs use the axle to separate the annular bearing assemblies and utilize attachment rings to provide a way to attach the hub to a wheel rim. However, the attachment rings of these designs are designed such that a hollow shell positioned over the axle is needed to prevent the attachment rings from slipping off of the bearing assemblies in an inward direction.
Users, and thus manufacturers of performance bicycles, demand optimal responsiveness from their bicycles when riding. The more a wheel hub flexes, the less responsive it will be. Flexibility of a wheel hub is due in part to the diameter of the wheel hub axle. An axle having a smaller diameter will flex more than an axle having a greater diameter. Many wheel hubs are designed with an axle having a diameter of between 8 and 9 millimeters.
From the foregoing, it will be appreciated that it would be an advancement in the art to provide a wheel hub where the bearing assemblies were separated and held in a spaced relationship by the axle.
It would be a further advancement in the art if the wheel hub could be attached to a wheel rim without the need for an exterior shell.
It would be an additional advancement in the art if annular brackets configured with means to prevent sliding off the bearing assemblies were used to attach the wheel hub to a wheel rim.
It would be still another advancement in the art if the bicycle hub were designed to permit axles having a greater diameter.
Such a wheel hub is disclosed and claimed herein.